Farmers tackling phosphate runoff

Agriculture is one source of phosphate in water (More toxic algae reported in waterways than usual, 6 August), but makes a much smaller contribution than human sewage – the dominant source. A 2006 study for Defra assessed the overall agricultural contribution as less than 30% of total phosphate, or less than 20% of phosphate in biologically active form. Moreover, most phosphate loss from farmland occurs in winter when levels of plant and algal growth are low.

Farming recognises that it contributes to the problem and is actively working to minimise its impact. Specifically, the industry promotes good nutrient practice through its Tried & Tested nutrient management scheme. Farmers' use of phosphate fertilisers has reduced by 43% in the last decade and 56% since the 1980s.

The NFU is currently working on a joint project with the Environment Agency to better understand and address the loss of phosphate from agriculture, including an independent review of the scientific understanding and two pilot catchments where there are plans to trial methods of achieving further reductions.

As for human sources, have we done all we can to reduce our use of phosphates in the home and conserve this precious and vital resource?